antifreeze for my car

Engine coolant is a technical fluid in the engine cooling system. It serves to dissipate the heat from hot engine parts and other units. It can also heat the air inside the vehicle.

Types

By composition:

• IAT (Inorganic Acid Technology): these are based on a water-glycol solution and non-organic additives, mostly phosphates, nitrates, and silicates. These additives, reacting with each other, create a protective film on the surfaces of the parts. Over time, their number is reduced, and elements of the system are exposed to corrosive influences. These coolants are often green or blue-green. Such compounds are inexpensive, but require more frequent replacement.
• OAT (Organic Acid Technology): these are a mixture of monoethylene glycol with organic additives – carboxylates. They have a longer service life. They provide excellent protection to system parts from corrosion and cavitation. They must not be mixed with other types of coolants. The products of this class are bright red, orange, or purple in colour.
• HOAT (Hybrid Organic Acid Technology): these products contain organic and inorganic additives. They are cheaper than the OATs and better protect from corrosion than IATs. They retain efficiency for several years of use. They can be different colours: pink, blue-green, but more often yellow or orange.
• Lobrid or SOAT (Low hybrid or Silicon enhanced Organic Acid Technology): along with organic additives, these contain silicon compounds. They have a higher boiling point – up to 135° C. They are perfect for highly loaded units. Such coolants are especially efficient for protection of aluminium radiators. They have a long service life and are usually bright red or purple in colour.
• Based on propylene glycol: these products are less poisonous than all the products noted above based on ethylene glycol. They contain organic corrosion inhibitors and are known for their long lifespan.

Operating tips

Replace the coolant within the recommended intervals. This directly affects the integrity of cooling system elements and its efficiency. Choose only products that are suitable for your vehicle. For instance, it is prohibited to use OAT and HOAT fluids in brass radiators. Never mix products of various classes, even if they are the same colour: as you can see, products with different contents can be the same colour. Replace the water pump on time. When topping up antifreeze, make sure that dirt doesn’t enter the coolant reservoir. Always water down antifreeze in the ratio recommended by the car manufacturer for your specific area.

Symptoms of deterioration

If the coolant turns a rusty colour, this indicates corrosion of the system's components and that corrosion inhibitors have stopped performing their function. Crust on the coolant reservoir walls in particular indicates deterioration of the fluid. It can result in clogging of the radiator and cooling channels, which generally affects the efficiency of the system. Thickening of the coolant usually indicates ingress of oil into the system. Freezing is caused by too high a concentration of water in the coolant.

Causes of premature deterioration

Coolant contamination is most often caused by wear-out of mechanical units of the cooling system, the water pump in particular. It can also be caused by careless use, for instance, by letting dirt get on the expansion reservoir cap during servicing. Products of corrosion, which can be caused by the use of components made of incompatible materials, such as aluminium and copper, can also lead to deterioration. The appearance of crust or sludge can be caused by mixing of inappropriate compounds or burning-out of a cylinder head gasket and ingress of oil into the cooling system.

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In our online shop you can buy suitable antifreeze for your car at any time. All our products are characterised by perfect quality, which we back up with a warranty.

Useful information on functions, causes of malfunction, diagnosis and replacement intervals

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